title: Safety, efficacy, and dosing of recombinant human bone morphogenetic protein-2 for posterior cervical and cervicothoracic instrumented fusion with a minimum 2-year follow-up.
abstract: BACKGROUND
  Considerable attention has focused on concerns of increased complications with recombinant human bone morphogenetic protein-2 (rhBMP-2) use for anterior cervical fusion, but few reports have assessed its use for posterior cervical fusions.
  
  
  OBJECTIVE
  To assess the safety, efficacy, and dosing of rhBMP-2 as an adjunct for instrumented posterior cervical arthrodesis.
  
  
  METHODS
  All patients treated by the senior author with posterior cervical or cervicothoracic instrumented fusion using rhBMP-2 from 2003 to 2008 with a minimum of 2 years of follow-up were included. Diagnosis, levels fused, rhBMP-2 dose, complications, and fusion were assessed.
  
  
  RESULTS
  Fifty-three patients with a mean age of 55.7 years (range, 2-89 years) and an average follow-up of 40 months (range, 25-80 months) met inclusion criteria. Surgical indications included basilar invagination (n = 6), fracture (n = 6), atlantoaxial instability (n = 16), kyphosis/kyphoscoliosis (n = 22), osteomyelitis (n = 1), spondylolisthesis (n = 1), and cyst (n = 1). Fifteen patients had confirmed rheumatoid disease. The average rhBMP-2 dose was 1.8 mg per level, with a total of 282 levels treated (average, 5.3 levels; SD, 2.8 levels). Among 53 patients, only 2 complications (3.8%) were identified: a superficial wound infection and an adjacent-level degeneration. No cases of dysphagia or neck swelling requiring treatment were identified. At the last follow-up, all patients had achieved fusion.
  
  
  CONCLUSIONS
  Despite many of the patients in the present series having complex pathology and/or rheumatoid arthritis, a 100% fusion rate was achieved. Collectively, these data suggest that use of rhBMP-2 as an adjunct for posterior cervical fusion is safe and effective at an average dose of 1.8 mg per level.
authors.affiliation: Department of Neurosurgery, University of Virginia Health System, Charlottesville, Virginia 22908, USA.
authors.forename: D Kojo
authors.initials: DK
authors.lastname: Hamilton
authors.forename: Justin S
authors.initials: JS
authors.lastname: Smith
authors.forename: Davis L
authors.initials: DL
authors.lastname: Reames
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Williams
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Chernavvsky
authors.forename: Christopher I
authors.initials: CI
authors.lastname: Shaffrey
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D055396:Bone Morphogenetic Protein 2 / Q000627:therapeutic use*; D002574:Cervical Vertebrae / Q000187:drug effects / Q000601:surgery; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011994:Recombinant Proteins / Q000627:therapeutic use; D012189:Retrospective Studies; D013118:Spinal Cord Diseases / Q000145:classification / Q000188:drug therapy* / Q000601:surgery*; D013123:Spinal Fusion / Q000379:methods*; D014057:Tomography, X-Ray Computed; D016212:Transforming Growth Factor beta / Q000627:therapeutic use*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D055396:Bone Morphogenetic Protein 2; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; C499469:recombinant human bone morphogenetic protein-2